Saturday, 18 June 2016

Beautiful Roll Cloud Rises Over Lake Michigan

Sent in by William Neu
Time-lapse shows huge cloud rising over Lake Michigan near the Sleeping Bear Dunes National Lakeshore.

A roll cloud is a low, horizontal, tube-shaped, and relatively rare type of arcus cloud.
They differ from shelf clouds by being completely detached from other cloud features.
Roll clouds usually appear to be "rolling" about a horizontal axis.
They are a solitary wave called a soliton, which is a wave that has a single crest and moves without changing speed or shape.
One of the most famous frequent occurrences is the Morning Glory cloud in Queensland, Australia, which can occur up to four out of ten days in October.
One of the main causes of the Morning Glory cloud is the mesoscale circulation associated with sea breezes that develop over the Cape York Peninsula and the Gulf of Carpentaria. However, similar features can be created by downdrafts from thunderstorms and are not exclusively associated with coastal regions.
Coastal roll clouds have been seen in many places, including California, the English Channel, Shetland Islands, the North Sea coast, coastal regions of Australia, and Nome, Alaska.

A rare and very unique "roll cloud" along the Lake Michigan shoreline at Sleeping Bear Dunes National Lakeshore. Video is 4x speed.